The Goddess has been summoning and reincarnating a broad range of people in order to stop the Hero from destroying the world, but they all seem to have ended in failure. However, all the reincarnations that had been conducted until now were for the purpose of gathering data. With the data she has gathered, she summons the person most likely to stop the Hero.
to suppress its side effects are 
astronomically small, which means...
...تأثيرها الجانبيّ ضعيفةٌ لحدٍّ العدم، مما يعني
ist astronomisch gering.
Das bedeutet also …
para evitar los efectos negativos
es casi nula, por lo que…
para evitar los efectos negativos
es casi nula, por lo que…
pour un humain ordinaire.
para suprimir seus efeitos colaterais
são astronomicamente pequenos, então...
подавляющую побочный эффект.